知识大全 jsp分页类－－－统一使用

Posted 2022-07-20 知

篇首语：知识是心灵的活动。本文由小常识网(cha138.com)小编为大家整理，主要介绍了知识大全 jsp分页类－－－统一使用相关的知识，希望对你有一定的参考价值。

　　一 建立数据库分页的类

　　package newsbean; import java sql *;

　　public class DBConnection //这里使用ms jdbc String sDBDriver = " microsoft jdbc sqlserver SQLServerDriver"; //指定数据库名/url private final String url = "jdbc:microsoft:sqlserver://"; private final String serverName= "localsqlserver"; private final String portNumber = " "; private final String databaseName= "MyBusiDB"; //String sConnStr = "jdbc:microsoft:sqlserver://localsqlserver: ;DatabaseName=ourpany"; private final String dbUserName = "sa"; private final String dbPassword = " "; // Informs the driver to use server a side cursor // which permits more than one active statement // on a connection private final String selectMethod = "cursor";

　　Connection conn = null; ResultSet rs = null; Statement stmt = null;

　　//这三个参数用于记录翻页 int iRowCount = ; //返回总行数 int iPageCount = ; //返回总页数 int iPage = ;

　　public DBConnection() try Class forName(sDBDriver); catch(ClassNotFoundException e) System err println("DBConnection():" + e getMessage());

　　//构造一个连接字符串 private String getConnectionUrl() return url+serverName+":"+portNumber+";databaseName="+databaseName+";selectMethod="+selectMethod+";";

　　//================考虑在类中的分页====================================== //内部设置总条数 private void setRowCount(int irowcount) this iRowCount = irowcount; //返回内部设置的总条数 public int getRowCount() return this iRowCount;

　　//内部设置总页数 private void setPageCount(int ipagecount) this iPageCount = ipagecount; //返回内部设置的总页数 public int getPageCount() return this iPageCount;

　　//内部设置当前页 private void setPage(int ipage) this iPage = ipage; //返回内部设置的总页数 public int getPage() return this iPage; //显示翻页信息 //参数 总页数 总行数 当前页 //应该考虑加一个查询参数列表进入本方法 public String showChangePage() return this iPage + "/" + this iPageCount + ">>>";

　　//考虑了翻页的选择查询 public ResultSet execQuery(String sql int iPageSize int iPage) //======iRowCount== iPageCount==iPageSize===iPage================ try conn = DriverManager getConnection(getConnectionUrl() dbUserName dbPassword); stmt = conn createStatement(ResultSet TYPE_SCROLL_SENSITIVE ResultSet CONCUR_UPDATABLE); rs = stmt executeQuery(sql); rs last();

　　//获取总行数 移动到最后 检索当前行编号 int iRowCount= rs getRow(); //计算总页数 总 行 每页 行===〉总页数= 页==> 页 int iPageCount = (iRowCount + iPageSize ) / iPageSize; if(iPage>iPageCount) iPage = iPageCount; if(iPage <= ) iPage = ; if(iPageCount> ) //在方法体中已经到了指定行 rs absolute((iPage ) * iPageSize + ); //自己设置iPageCount和iRowCount iPage 避免混淆？！ setPageCount(iPageCount); setRowCount(iRowCount); setPage(iPage); //stmt close();??? //end try catch(SQLException ex) System err println("DBConnection execQuery():" + ex getMessage()); //end catch

　　return rs;

　　//end execQuery

　　//====================================================== //关闭数据库 public void closeDB() try

　　//System out println("DBConnection closeDB( here!)" ); if(rs!=null) rs close(); rs = null; else System out println("rs closed!"); //?????

　　if(stmt!=null) stmt close(); stmt = null; else System out println("stmt closed!"); if(conn!=null) conn close(); conn = null; else System out println("conn closed!"); catch(Exception ex) //System err println("DBConnection closeDB()" + ex getMessage()); System out println("DBConnection closeDB()" + ex getMessage());

　　 //end Class

　　二 jsp程序中使用本类过程 <jsp:useBean id="conn" /> 处理查询参数iPage txtSearchKeyword等 文章列表

　　int iPageSize = ;//每次读行数 作为参数传入<jsp:setProperty id 没用上！ String sql=null; ResultSet rs =null; int iRowCount = ; int iPageCount = ; try //=========================== int i = ; //l构造sql语句 sql="SELECT top number sms_no pany_card_name Reg_Date Dead_Date OnUse province " + "City FROM dbo Company_Card where=" ; if(!( txtSearchCompanyCard equals("")))sql = sql + " and pany_card_name like %" + txtSearchCompanyCard + "% "; if(!( txtSearchCity equals("")))sql = sql + " and City=" + txtSearchCity + " "; sql = sql + " order by number desc ";

　　//取得resultset rs = conn execQuery(sql iPageSize iPage);

　　//获取记录总数 iRowCount = conn getRowCount(); //获取总页数 iPageCount = conn getPageCount();

相关参考